TY - JOUR
T1 - Mitochondrial Iron Transporters (MIT1 and MIT2) Are Essential for Iron Homeostasis and Embryogenesis in Arabidopsis thaliana
AU - Jain, Anshika
AU - Dashner, Zachary S.
AU - Connolly, Erin L.
N1 - Funding Information:
We are grateful for funding from NSF IOS (award 1456881) and NSF PGRP (award 144435). We would like to thank Dr. David Salt and John Danku for ICP-MS analysis of Arabidopsis plants, Dr. Jerry Kaplan for the pRS426-ADH vector and the mrs3mrs4 yeast strain and Dr. Janneke Balk for the aconitase antibody and for her help with BN-PAGE experiments.
Publisher Copyright:
© Copyright © 2019 Jain, Dashner and Connolly.
PY - 2019/11/25
Y1 - 2019/11/25
N2 - Iron (Fe) is an essential nutrient for virtually all organisms, where it functions in critical electron transfer processes, like those involved in respiration. Photosynthetic organisms have special requirements for Fe due to its importance in photosynthesis. While the importance of Fe for mitochondria- and chloroplast-localized processes is clear, our understanding of the molecular mechanisms that underlie the trafficking of Fe to these compartments is not complete. Here, we describe the Arabidopsis mitochondrial iron transporters, MIT1 and MIT2, that belong to the mitochondrial carrier family (MCF) of transport proteins. MIT1 and MIT2 display considerable homology with known mitochondrial Fe transporters of other organisms. Expression of MIT1 or MIT2 rescues the phenotype of the yeast mrs3mrs4 mutant, which is defective in mitochondrial iron transport. Although the Arabidopsis mit1 and mit2 single mutants do not show any significant visible phenotypes, the double mutant mit1mit2 displays embryo lethality. Analysis of a mit1−−/mit2+− line revealed that MIT1 and MIT2 are essential for iron acquisition by mitochondria and proper mitochondrial function. In addition, loss of MIT function results in mislocalization of Fe, which in turn causes upregulation of the root high affinity Fe uptake pathway. Thus, MIT1 and MIT2 are required for the maintenance of both mitochondrial and whole plant Fe homeostasis, which, in turn, is important for the proper growth and development of the plant.
AB - Iron (Fe) is an essential nutrient for virtually all organisms, where it functions in critical electron transfer processes, like those involved in respiration. Photosynthetic organisms have special requirements for Fe due to its importance in photosynthesis. While the importance of Fe for mitochondria- and chloroplast-localized processes is clear, our understanding of the molecular mechanisms that underlie the trafficking of Fe to these compartments is not complete. Here, we describe the Arabidopsis mitochondrial iron transporters, MIT1 and MIT2, that belong to the mitochondrial carrier family (MCF) of transport proteins. MIT1 and MIT2 display considerable homology with known mitochondrial Fe transporters of other organisms. Expression of MIT1 or MIT2 rescues the phenotype of the yeast mrs3mrs4 mutant, which is defective in mitochondrial iron transport. Although the Arabidopsis mit1 and mit2 single mutants do not show any significant visible phenotypes, the double mutant mit1mit2 displays embryo lethality. Analysis of a mit1−−/mit2+− line revealed that MIT1 and MIT2 are essential for iron acquisition by mitochondria and proper mitochondrial function. In addition, loss of MIT function results in mislocalization of Fe, which in turn causes upregulation of the root high affinity Fe uptake pathway. Thus, MIT1 and MIT2 are required for the maintenance of both mitochondrial and whole plant Fe homeostasis, which, in turn, is important for the proper growth and development of the plant.
UR - http://www.scopus.com/inward/record.url?scp=85076697218&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85076697218&partnerID=8YFLogxK
U2 - 10.3389/fpls.2019.01449
DO - 10.3389/fpls.2019.01449
M3 - Article
C2 - 31850005
AN - SCOPUS:85076697218
SN - 1664-462X
VL - 10
JO - Frontiers in Plant Science
JF - Frontiers in Plant Science
M1 - 1449
ER -